I have racing C4 Corvettes in Solo II autocrosses, open track events and now SCCA road racing. Camber braces are required on unibody chassis where the spring and shock mount is high up and its possible for the unibody to deflect under load. A brace is required in that situation. Now look at a C4.
The spring loads are transferred to the K member cross brace and the shock
brackets are welded to the frame. I run 315/35/17 Kumho Victoracers on 7 x 11 GS rims up front, Koni sport shocks and a an adjustable reinforced 30 mm
sway bar on my race car, ex street, ex solo 90. As an engineer, from a practical perspective, I can see no need for a camber brace. My car has more cornering power than any street driven car and it handles great on the track without a brace. I haven't seen any C4 race car with one. The thing must weigh a ton and the last thing a C4 needs is more weight up front. Most people would be better off going to a junk yard and buying the Z-51 K member braces. I honestly believe those people who have bought them and say they make the car handle better honestly believe it. That have to justify in their minds having spent several hundred dollars to buy it. Has any one been shown any proof or done pre and post installation track time testing to prove the brace really works? If so please post your results. My personal opinion is its smoke and mirrors. :lol: :lol: :lol: :lol: :lol:

 

Man you are brave, you will get nuked for that post. :) I agree, on a C4 with stock suspension it is dead weight in the wrong place. I think the problem with a stock C4 is that no matter how stiff you make the towers you have control arm bushing that are very soft with a lot of flex. Not to mention wheel bearings that on many occasion have an 1/8" of play out of the box. If you had to have that thing to win you would see it on the top cars in BSP. I see it on ZERO of the top national solo2 drivers cars. There are a lot of top solo2 SP class cars that have strut suspension that do not use a brace, no one wants extra weight on the front. As far as data who are you to question the mighty butt dyno. You know you can not argue with the butt dyno. Not only does it stiffen the front it is worth 20hp. ;) Seriously I could see some benefit to a car with coil-overs and stiffer bushings, but not on the stock suspension. I guess we will see if any fast cars show up in Topeka with one...... :seeya


[Modified by RX7 KLR, 10:51 AM 7/5/2003]

 

:confused: ......... what the heck? now I'm wary of buying something that almost every person on this forum whose gotten one has said it really improved things. gj, now look at what you did. :p:

 

Let me toss this into the fire. In this picture, is the main white crossmember non-existant on non Z51/Z52 cars, or is it simple just not AS stiff.




[Modified by scorp508, 2:14 PM 7/5/2003]

 

Doh.... NM.. I was thinking cross brace, not camber. Just pretend I wasn't even here....

:leaving:


[Modified by Preacher, 2:19 PM 7/5/2003]

 

This is goig to be a nice day. :skep:

 

Didn't they add the Z51 Kmember to the latter C4s? My 90 vert has it. Or did they add just to the convertibles? :confused:

 

It weighs .0045 tons or 9 lbs. :D Here is a discription with pics from the seller about how it helps. http://www.r-dracing.com/Camber-brace.htm

 

It could be partially due to the placebo effect. Everyone would like to believe there mod made a difference and was worth every penny they spent, but if you believe every add as is states gains we should be driving 500hp L98's with only bolt ons that get 40mpg. A true test of the camber brace is not "I was 2nd last month at the autox then I got the brace and was 1st at the next event". Or :I was lapping VIP at 1:22 last month and then I got the brace and this month I am at 1:21". To many variables to get real results that way. Without data accusation or a shaker jig the only reasonable method is a blind test. Many tire test are done this way, put the driver in the car and don't tell them what tires they have, or in this case do not tell them if they have the brace or not. I would imagine you would see little if any difference in lap times. From my own experience with a data recorder on board: Kumho MX street tires VS Kumho Victoracers, I could feel a major difference, showed up on the computer as 1.03 VS 1.24 lg. Exhaust: changed my cat back system, sounded different but could not feel it, made 4hp and 18tq on the dyno. I have also had people co-drive my car at events, they complained of the car being loose or tight when I thought it was fine. So pretend to make a change and put them back in the car, 9 times out of 10 they say "oh that is better you got it now", placebo. None of us are as in tune as we would like to think. Show me the numbers. :cheers:

 

If you read the thread about the Camber Brace, posted a few weeks ago, most of the people state that it keeps the car from being slung around in the highway ruts, and reduces the creeking associated with our cars. For me, that's reason enough to buy it. I don't do autocross, so I would never be able to say whether it improves lap times, but be rest assured it will be waiting at my house when I get home.

As a side note, people seem to underestimate the judgements of the "SOTP scientific method" :D. If you are used to the way your car handles and it's little quirks and whatnot, then mod it somehow, and can really tell that your car acts differently, then chances are that mod improved what it was meant to, especially in the case with a mod like this. Also, I don't think so many people would overwhelmingly state the same positive effects if the Camber Brace did not work. Yes, you will get those who install a part and swear up and down it helped, especially when it comes to a horsepower-type part. But, as I said, when so many people agree as to the effects of this particular mod, I would tend to believe it really does work.

 

I would have to agree with Larrybsp.

This is not to take away from anyone who's put the camber brace on their cars, nor from the guys at R-D Racing who make the brace, but I'm an engineer as well and the only thing that speaks volumes are real numbers.

I read a post from someone last month who took his brace off and said the car handled terribly. Great comment in favour of the brace, but without numbers it's just opinion really. If it's easy to remove, surely someone here can pull theirs off during their next track event for a couple of laps just to compare numbers with and without. In fact, I'm surpirsed that the guys at R-D Racing haven't done it by now.

So how about it - anybody with the camber brace willing to step up to the plate and prove to us that it's worth its weight/cost/installation effort?


[Modified by TheCorvetteKid, 2:58 PM 7/5/2003]

 

Please keep in mind I am not trashing the product, I think it is a great innovative idea that has its place. I do think that the results on a stock car are very overrated, just like most of mods on the market. :crazy:

 

Do you agree that it might help with stability of the front end by reducing the flex?

 

Not on a stock car. Maybe on a car with solid bushings or coil-overs. :nonod:

 

Edited:...The white bar above the steering rack on my NON-Z51 '86 measures 2" x 3" x ~.085"...And it has the two small 45* braces, but not the sidebar extensions (between the frame & the 45* braces, in white)...


[Modified by Rich B., 4:55 PM 7/5/2003]

 

OK, I just got back from a vacation hustling the car around on REAL-World nasty bumpy two lane roads in PA. You engineer guys see no benefit on race track or autocross surfaces. Agreed.

But with the Camber Brace and the new Z51 Bilsteins on my 94 I can blast hard trough bumpy turns and the tires keep their grip as well as they formerly did on glass smooth roads (like Rt 211 in VA). How many people here dread coming up on a series of bad bumps in mid-corner? No worry with the Camber brace and top-notch shocks.

Some of us drive these things fast on real roads and don't reserve our fun for special glass smooth surfaces. For us the camber brace is well worth it.

The Cross Bar helped some, but with the top off there is still some upper body shake over bad bumps. Way less than before, but still some there.

I would recommend the camber brace for anyone who loves to hustle over country two lanes in the East. For reference you might check with the Pennsylvania Hill Climb Association. I hit the road up from Trout Run that they race. Not billiard table smooth. The first road I hit in a hurry was Elimsport mountain, I took it faster than I imagined possible. Couldn't do that last year.

 

I believe RX& KLR said it best " I think the problem with a stock C4 is that no matter how stiff you make the towers you have control arm bushing that are very soft with a lot of flex. Not to mention wheel bearings that on many occasion have an 1/8" of play out of the box. If you had to have that thing to win you would see it on the top cars in BSP. I see it on ZERO of the top national solo2 drivers cars. " Having run against many of those same top Solo II BSP drivers, Guy Ankenny, Rita Whilsey, Jeff Glorioso, Gary Tomlinson etc. I agree. These are very savvy Corvette drivers and preparers. If the brace was useful it would be on all their cars. As a side note,
I road race my C4 with the stock Z51 rubber bushings quite successfully. I use the bushings for practical not performance reasons. I would love to go to stiffer bushings but when road racing you're going to off track or hit a berm
sooner or later. I'd rather not break a suspension part at that instant so I leave the bushings in for compliance to absorb the shock. I know it pays off because I was forced off the road at Buttonwillow and hit something so hard
I dished the passenger side shock tower from the impact. Without some compliance I probably would have broken a ball joint or worse. I do agree with someone elses comment to the effect that if the camber brace does improve performane, why don't the advertise the test data to back their claims? Fair enough question. :rant: :rant: :rant:

 

Let me sum up what's been said so far...

- Those that don't have one speculate it doesn't work.
- Those that do have one speculate or perceive it does.

Unfortunately, short of staggering numbers, any real improvement or lack of improvement will be caveated with "if the car was running better" or "if the weather wasn't so lousy" or "if the track was better prepared" or "the track was really good initially" or "the engine was running great for that run" or ...

Likewise statements such as...
"lt gives a tighter feel to the car" or "The car tracks less" or the car has fewer squeaks" will be dismissed as SOTP feel good stories.

Lastly the "I'm an engineer. Prove to me it works" can also be turned around. I'm an engineer, prove to me that it doesn't.

Not that it matters, but I think it gives the car a tighter feel. I reached that conclusion after driving a '96 with one and then immediately driving my '96 *without* one. A friend *without* one on his '94 drove my GS and came to the same conclusion. This tends to dismiss the "wallet talking" theory. I'm sure there are other examples of people test driving prior to buying. I'd be curious to hear from those that ultimately did or didn't buy after test driving and why they made the choice they did.

Yeah...this thread is just what we need on a lazy Saturday afternoon. :D

 

Torch, I could not think of a worse testimonial for the camber brace than to say you just put on new shocks and a camber brace. That is what shocks do, they keep the tire on the road, if you had bad ones you will see a huge improvement with new shocks. As far as smooth surfaces, I guess you have never seen Forbes field in Topeka, the North course for the solo2 nationals is like going off road. :thumbs:

 

RX7 KLR, You sound like you really don't like this product. What got you started on this campaign?